1. Field of the Invention
The present invention relates to a rotary piston internal combustion engine having an oil-cooled piston slidably journalled and having a housing which consists of two side parts and a casing mantle part with dual-arc trochoidal-shaped casing mantle runway inner surfacing and having an eccentric shaft journalled in the side parts passing axially through the housing. The triangular piston mounted on the eccentric of the eccentric shaft rotates as controlled and regulated by a synchronous transmission gear drive unit which is provided in the piston between the eccentric and one of the side parts. The synchronous transmission gear drive unit is formed by a hollow gear stationary as secured on the piston and a pinion stationary as secured on the housing located around the eccentric shaft.
2. Description of the Prior Art
Conventionally the lubricating- and cooling-oil with such machines is supplied via axial and radial bores in the shaft into the slide bearing of the eccentric and from there into the cooling hollow chambers of the piston as well as directly into the transmission gear drive unit and to the outer side of the piston. Both the bearing lubrication as well as the cooling of the piston require a very considerable through-passage or volume of oil that is under pressure, which penetrates between the piston- and housing-sidewalls and there having to be kept away from working chambers and the combustion procedures by oil inner seals which are so-called scraper rings, in order not to cause any intolerable exhaust or waste gas values. The oil inner seals however are costly and complex and moreover not reliable. Furthermore the oil inner seals require structural space between the hollow gear of the transmission gear drive unit and the axial gas seals and accordingly restrict and narrow space available for other constructive possibilities.